All steel hot air furnace



June 27, 1933 F. H. MILLER ET AL ALL STEEL HOT AIR FURNACE 4Sheets-Sheet 1 Filed May 25, 1931 m T M V J T ATTORNEKS June 27, 1933.F. H. MILLER ET AL ALL STEEL HOT AIR FURNACE 4 Sheets-Sheet 2 Filed May25, 1931 INVENTORS A TTOR/VEVJ June 27, 1933. F. H. MILLER ET AL ALLSTEEL HOT AIR FURNACE 4 Sheets-Sheet 5 Filed May 25, 1951 Z .Y B

JOAMTJW ATTORNEYS June .1 F. H. MILLER ET AL ALL STEEL HOT AIR FURNACE 4Sheets-Sheet 4 Filed May 25, 1951 FIG; 6.

3 wi'thpartof thefront wall removed.

5 F1gure 3; I

Patented June 27, 1933 FRANKLIN H. MILLER 'A'Ni) YWJ-FIILELI'IAM EM;snorrivnn, on payroll; o rro A p ilieati o'n fiiee' ma 25,1931; swarm.539,776;

- This invention relates'to improvements in furnaces, and hasforitsobject to pro'vide an improved, all steel hot air furnace.

It is particularly the object of this inven- 5 tion to provide anfallsteelhot air furnace in which there iswan external case within which islocated a heating chamberor drum,. t g

I 'j-The tOPJSlIlCllHQd mwardlyto'wardthe which has thereinf'a removablegrate mem'-. ber.

so that a current? of. air-and gases imayv be 7 maintained withoutcausing an undue un-z; necessarycombustion ofthe fuel in the. furnaceand on the grate.

combustion chamberforproviding agas passageway. for heating thea1r 1nthe air chamher as itrises. This gasjpassageway i .7 formedso'thatitwillofferzthe'least'resistance and an open1n'g'8 fortheadmissloniof fuel: and removal of ashes and for-the purpose of draft,the case is of one continuous solid to vthe rising air, in the airChamber and. form the greatest amount-of contacting surface for the airwhereby itmay be more readily and completely heated.

3Q These and other advantages will appear from the following descriptiontaken in con nection with the drawings.

Referring to the drawings: 7 Figure 1' is a front elevation of thefurnace Figure Qflis a Vertical section through the furnace showingthe'relative positions of the 7 case and the combustion chamber-locatedwithin the caseand-the-air chamber between the case and the combustionchamber;

FigureS is a sectionon the line 3 3 of Figurel. 7

Figure 4 is a section on the line ,of

Figure, 5.is a view similar to Figure 2 showing the upper end ofthecase, With'theheatingflue inreverse positlon tothat shown.

in Figure-2;

7 Figure 6'isa View showing detail there movablegrateunit. 1 a

It is also an object of this inventionto pro-. vide, in connectlon wlthan a1r furnace, means; to admit air into-the furnace abovethe grate'withflues, later to be described.

The furnace is more or 'lessrectangular in i :shape,=and has a frontwall 1, side walls'2,\aback 3, abottom 4 anda top 5., all composed ofsheet metal'and so united that there is an 5 all steel'caseflforming theouter, walls o-f'an 5 air chamber and supports for a combustionchamherand grates.

ingg'air in 'the chamber' towardgthe outlets a i i for the hot air in.the upperend'of theychamber. These outlets; are indicated by the nu-'meral 7 aildmay be any number. In Figures l and, 2 theoutlets are'shown.In'ord'erzto at the lower or bottom end of-the case; The". inlets andoutlets may be. used for the-recirculation'bf air 'fromthe, room,through case-land" back into the room, or they may-be supply fresh air.there are provided inlets 6 through the. outlets.

' With the exception of the outlets and inlets L of they case. It issubstantiallyrectangular in shape and has a rear wall 10 andside walls11. i The rear wall slopes upwardly andtoward the front as indicated bythe numeral 12, and passes into a downwardly inclined part 18 ofthefront wall of the firesbox and drum." This construction of the firebox is well illustrated in Figure 2: v v At the extreme upper curved endof the fire box and drum are two outlet openings 14, which serveas-draft holes andcommunicate Around the front of the fire box and drumis a frame 15 suitably attachedto the front wall 9 by means of rivets,bolts or other suitable meansv This" frame has. three openings-therein.The lower closed by an ashdoor 1,6, in which there is a opening,- nextto :the bottom of the case, is

20, while on the door 19 this slide is indicated by the numeral 21.These slides are for the purpose of admitting air into the drum part ofthe fire box, or that part of the fire box above the combustion chamber.I

The openings or outlets 14; pass into arms 22 of a- U shaped heatingflue supported around the upper end of the fire box and drum. The openends of this tl-shap-ed heater project through the front wall of thecase, as indicated in Figure 1, and are closed by doors 23. These doorsare for the purpose of enabling the removal of ashes and Cinders andother solid material that collect in the heating flue.

In the arm of the heating flue. adj acentan opening 14: is an inletopening 24 in line with the opening 14:. Between the sides of the firebox and drum and the adjacent sides of the arms of the heating flue is apipe 25, which has on each end a flange 26. This pipe fits around: theholes 1st and 24with the flange against the walls. Opposite the pipe andat. tach-ed to each of the-walls 11 and the inside Wall of each arm ofthe heating flue is a ring 27 These rings are fastened to the flanges 26by means of rivets or any other suitable means. i The relative positionsof the, parts are shown in Figure 3.

The hot air and gases rise from the com bustion or fuel chamber, passinto the upper part of the combustion chamber or drum, and out throughthe openings 14 into the arms 22 of the heating flue. The closedend ofthe U- shaped heating flue is enlarged, as indicated by the. numeral 28,and has extending outwardly therefrom an outlet opening 29 which leadsinto a stack or flue by which the draft is produced. Adjacent the outlet29 is a trap 230, closed by means of a door 31. The p'ur pose of thistrap is to catch ashes, cinders and other solid material that may becarried.

along with the gases and the hot air passing from the combustionchamber.

The U-shaped heating flue may be arranged in a reverse position to thatshown in Figure 2 and in the position shown in Figure 5. As shown inFigure 5, the trap 30a extend-s upwardly and may project through thewall of the case adjacent the heating flue, or a pipe 30?) may beattached to this trap and extend across the uppere'nd of the'case andout through thefront wall thereof,- above the doors. Tn either event,the smoke stack or smoke flue is attached to the outlet end of the trap30a. When the trap 30a is used for forming part of the draft channel theopening 29a is used for cleaning purposes and may beclosed by a doorsimilar to that shown in Figure 2 and indicated across the top of thecase but within the case,i

there is an increased amount of heating surface over which the airpasses beforeleau ing the. air inlets, thereby increasing the" heatingeffectof the furnace. By arranging the heating flue in the positionshown in" Figure 5 not only is .the heating area increased but means isprovided for attach I ng the outlet fluein another positlon so" that thefurnace may be more readily and satisfactorily adjusted with relation tothe parts of the room or basement in which it is located. i

Figure 6 shows a. plan view'of a removable grate unit adapted .to beused with the furnace described herein. This grate unit may be placed inand removed from the fire box through the fuel doors For supporting thegrate unit the fire box has suitable'ledges for seating the frame 32a ofthe grate; This frame is flat and rectangular in shape haw ing verticalgrate supporting flanges 32.

The grate is a removable-grateand hasend a trunnion 3 1 which fits ina'notch 35" inv the upper edge of one of theside flanges 32.

Each grate has extending downwardly therefrom an arm 36, and attached tothe lower end of each arm isa link 37 which-extends out through thefront of the furnace. The outer end of this link hasattachedthera to thelower end of a lever 38, pivoted intermediate its ends at a point 39 sothat by operating the" lever the grates may on their trunnions. V j

As shown in Figure 2 the grates are in a horizontal position, but byoperating the le ver 38these grates may be tilted so that ashes,clinkers and the} like accumulated thereon may be dumped in the ashchambe ribeneath the grates. Associated with the fire box and cn'eac'hside of the grates is a protecting wall be rocked edge of the fueladmission door a ledge 41,. which tends to divert the risinggasesandheat from the door above the fuel admission door.

a great amount of circulation of gases is desired Without increasing theamount of fuel gases burned, the slide door in the door 19 may beopened'so that air is admittedinto the upper" part of the drum orcombustionchamber. This air coming '11 through this door contacts'Wlth'tllfi r sing gases from the fueland becomes thoroughly mixed withthese gases, due to the restricted nature of the opening throughwhichjthe gases and air i pass. Not only is there an added quantity ofgas for circulation and, heating purposes- Without an increase in thecombustion. of v I sheet steel fire box and drum in sa d case fuel,-butif any unconsumedjor unburned may be rising'from the fuel on the gratestlns gas, onaccount of the excessive be consumed, thereby ,creating' agreater amount of heat .Without increasing the;

amount of fuel burned} It frequently happens When an insuflicie ntamount of air is admitted to burnin fuel that carbon monoxide isproduced, and Lin-,-

less burned Will pass into the air Without bemg consumed, but if theproper amount of air is added at theproper time and place this top, aU-shaped heating fiue in said case with ga'swill be converted intocarbon dioxide, thereby increasing the amount of-heat Without increasingthe amount of fuel consumed. The taking in of the air is due to injectoreffect due to the rising gases in the combustion chamber or drum. 7

We desire to comprehend Within our invention such modifications as maybe embraced Within-our claims and the scope of our invention.

c ,Having thus fully describedour invention,

what We claim as new and desire to secure by Letters Patent, is: a a

1. In a furnace, an integral sheet steelcase having air inlets and airoutlets, an integral sheet steel fire box and drum in said caseformingtherewith an air chamber,the side Walls of the drum front andrear Walls of said drum converging to form the top of: the drum, and aheat flue in said air chamber connected to opposite,

sides of the drum adjacent the top thereof. H

2; In a furnace, an integralsheetsteel case having air inlets andoutlets, a'hea-tiiig chamberin said case forming'with the case an airchamber, said heating chamber having vertical. side walls and upwardlyand inwardly inclined front and rear walls forming a curved I its armson opposite sidesof and connected WVhenever the furnacce is in operationand to the flue above being vertical and thetures.

to theheating chamber adjacent thetop and the walls of the case, acleansupported by ing .door in each arm outside "of, the case, and anoutlet from said heating flue through the back'wallof the case. i

having air inlets and air outlets, an integral sheetsteel fire box anddrum in said case forming therewith an air chamber, the side 'Walls ofthe drum being vertical-and the front and rear walls thereof convergingto form the top .of the drum, a heat fine in said air chamber connectedto opposite sides of the drum adjacent the top ther.eof,said flue havingan outlet through the back of the case and a trap connectedtothe'fiueadjacent the outcas'e. I

. .4. In a furnace, anintegral sheet metal case- 1 having air inlets andair outlets, an integral 3. In a furnace, an integral sheet metal case;I i

let and extending through the back of the] forming therewith anairchamber, the side e the back of-the case, and a'trap extending from theflue through. the back beneath, the finer, e a

5. In 'a furnace a sheet metal'case having air'inlets and air outlets, asheet metal fire box :and drum in said case forming therewith an airchamber, the side Walls oft'h'e drum beingvertical and the, front andrear Walls *the'reofvconverging to form the top ofthe drum,a heat fluein said airchamber connected to opposite sides of the drum adjacent thetop thereof, said flue havinga clean-outv opening extending through theback of the case, and adraft pipe connected at one'end the clean-outopening and having, its other end extending through the front Wall ofthe case.

6. In a furnace, a sheet metal'case having airinlets and air outlets, asheet metal fire box and drum in said case forming therewith an airchamber, the side Walls of said drum beingvertical and the front andrear Walls drum, a U-shaped-heat flue insaid aircham- :front wall of thecase, a cleaning door in each arm,and a draft pipeconnected at one endto the rear end of the U-shaped flue'and extending through the frontWall of the case,

In testimony whereof, wfe, affix our signa .FRANKL IN H; MILLER. 1

I WILLIAMM. snorrnnn; :1

115 '1 thereof converging toform the top of the

